/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.util;

import java.io.File;

/**
 * This StringParser can create StringMatcher instances for regular expressions matching file names. The regular
 * expressions can contain the following wildcards: '?' for a single regular file name character, '*' for any number of
 * regular file name characters, and '**' for any number of regular file name characters or directory separator
 * characters (always including '/').
 *
 * @author Eric Lafortune
 */
public class FileNameParser implements StringParser {
    // Implementations for StringParser.

    public StringMatcher parse(String regularExpression) {
        int index;
        StringMatcher nextMatcher = new EmptyStringMatcher();

        // Look for wildcards.
        for (index = 0; index < regularExpression.length(); index++) {
            // Is there a '**' wildcard?
            if (regularExpression.regionMatches(index, "**", 0, 2)) {
                // Create a matcher for the wildcard and, recursively, for the
                // remainder of the string.
                nextMatcher = new VariableStringMatcher(null, null, 0, Integer.MAX_VALUE,
                    parse(regularExpression.substring(index + 2)));
                break;
            }

            // Is there a '*' wildcard?
            else if (regularExpression.charAt(index) == '*') {
                // Create a matcher for the wildcard and, recursively, for the
                // remainder of the string.
                nextMatcher = new VariableStringMatcher(null, new char[] {File.pathSeparatorChar, '/'}, 0,
                    Integer.MAX_VALUE, parse(regularExpression.substring(index + 1)));
                break;
            }

            // Is there a '?' wildcard?
            else if (regularExpression.charAt(index) == '?') {
                // Create a matcher for the wildcard and, recursively, for the
                // remainder of the string.
                nextMatcher = new VariableStringMatcher(null, new char[] {File.pathSeparatorChar, '/'}, 1, 1,
                    parse(regularExpression.substring(index + 1)));
                break;
            }
        }

        // Return a matcher for the fixed first part of the regular expression,
        // if any, and the remainder.
        return index != 0 ? (StringMatcher)new FixedStringMatcher(regularExpression.substring(0, index), nextMatcher)
            : (StringMatcher)nextMatcher;
    }

    /**
     * A main method for testing file name matching.
     */
    public static void main(String[] args) {
        try {
            System.out.println("Regular expression [" + args[0] + "]");
            FileNameParser parser = new FileNameParser();
            StringMatcher matcher = parser.parse(args[0]);
            for (int index = 1; index < args.length; index++) {
                String string = args[index];
                System.out.print("String             [" + string + "]");
                System.out.println(" -> match = " + matcher.matches(args[index]));
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}
